package servlet;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Random;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import java.util.List;

import dao.JDBCUtil;

public class LoginServlet extends HttpServlet{
	//处理post类型的请求，request请求，response响应
	public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException {
		//获取请求里的参数
		String username=request.getParameter("username");
		String password=request.getParameter("password");
		String sql="SELECT * from employee where username=? and password=?";
		List params=new ArrayList<>();
		params.add(username);
		params.add(password);
		ResultSet rSet=JDBCUtil.execQuery(sql, params);
		
		try {
			if(rSet.next())
				response.getWriter().println("login success");
			else {
				response.getWriter().println("login fail");
			}
		} catch (SQLException | IOException e) {
			// TODO 自动生成的 catch 块
			e.printStackTrace();
		}
		
		
		String Code = request.getParameter("verifyCode");
		String randStr = (String)request.getSession().getAttribute("randStr");
		if(!Code.equals(randStr)||Code==null) {
			System.out.println("验证码错误");
			return;
		}
		System.out.println(username);
		System.out.println(password);
	}
	public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException,IOException {
		// 在内存中创建图象
				int width = 110, height = 30;
				BufferedImage image = new BufferedImage(width, height,
						BufferedImage.TYPE_INT_RGB);
				// 获取图形上下文
				Graphics g = image.getGraphics();
				// 生成随机类
				Random random = new Random();
				// 设定背景色
				g.setColor(getRandColor(200, 250));
				g.fillRect(0, 0, width, height);
				// 设定字体
				g.setFont(new Font("Times New Roman", Font.PLAIN, 20));
				// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
				g.setColor(getRandColor(160, 200));
				for (int i = 0; i < 155; i++) {
					int x = random.nextInt(width);
					int y = random.nextInt(height);
					int xl = random.nextInt(12);
					int yl = random.nextInt(12);
					g.drawLine(x, y, x + xl, y + yl);
				}
				// 取随机产生的认证码(6位数字)
				String sRand = "";
				for (int i = 0; i < 6; i++) {
					String rand = String.valueOf(random.nextInt(10));
					sRand += rand;
					// 将认证码显示到图象中
					g.setColor(new Color(20 + random.nextInt(110), 20 + random
							.nextInt(110), 20 + random.nextInt(110)));
					// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
					g.drawString(rand, 13 * i + 6, 16);
				}
				// 图象生效
				g.dispose();
				
				try {
					ImageIO.write(image, "JPEG", response.getOutputStream());
				} catch (Exception e) {
					System.out.println("验证码图片产生出现错误：" + e.toString());
				}
				//保存验证码到Session
				request.getSession().setAttribute("randStr", sRand);
	}
	private Color getRandColor(int fc, int bc) {
		// TODO 自动生成的方法存根
		Random random = new Random();
		if(fc>255)
			fc=255;
		if(bc>255)
			bc=255;
		int r = fc+random.nextInt(bc-fc);
		int b = fc+random.nextInt(bc-fc);
		int g = fc+random.nextInt(bc-fc);
		return new Color(r,g,b);
	}
}
